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a(1)=2, a(2)=5, a(3)=3; for n>3, a(n) is the smallest prime that has not already appeared and ends with the first digit in a(n-1) that equals 1, 3, 7 or 9.
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%I #24 Nov 07 2023 03:16:47

%S 2,5,3,13,11,31,23,43,53,73,7,17,41,61,71,37,83,103,101,131,151,181,

%T 191,211,241,251,271,47,67,97,19,281,311,113,331,163,401,421,431,173,

%U 461,491,29,59,79,107,521,541,571,127,601,631,193,641,661,691,89,109

%N a(1)=2, a(2)=5, a(3)=3; for n>3, a(n) is the smallest prime that has not already appeared and ends with the first digit in a(n-1) that equals 1, 3, 7 or 9.

%C Using Sierpiński's theorems [Sierpiński] (see also [Trost]), it is easy to see that the sequence is a permutation of the sequence of primes (A000040).

%D W. Sierpiński, Sur l'existence de nombres premiers avec une suite arbitraire de chiffres initiaux, Le Matematiche Catania, 1951.

%D E. Trost, Primzahlen, Verlag Birkhäuser, 1953, Theorems 20 - 21.

%H Peter J. C. Moses, <a href="/A262373/b262373.txt">Table of n, a(n) for n = 1..5000</a>

%Y Cf. A000040, A249974.

%K nonn,base

%O 1,1

%A _Vladimir Shevelev_, Sep 20 2015

%E a(46) corrected by _Peter J. C. Moses_, Sep 24 2015